Comment on Farooq's review:

good lightweight layer

Familiarity:
I've put it through the wringer

Fit:
True to size

I'm 6'2 and 200 and the large fits well. It is a very thin layer...my chest hair sticks through everywhere, but it is warm enough. I ended up cutting the sleeves down to 3/4 length and use it under my dress shirts in cold weather.